Ring inserts for dip tubes



July 8, 1958 F. v. BOYLAN RING INSERTS FOR DIP TUBES Filed Feb. 25, 1954FIG.2.

jhvenf or Frank V. Boylan By/Q/ RING INSERTS FOR DIP TUBES Frank V.Boylan, New Orleans, La., assignor to Marine Controls Laboratories, NewOrleans, La., :1 registered parmership of Louisiana Application February25, 1954, Serial No. 412,417

8 Claims. (Cl. 138-47) This invention relates generally to means forcoupling tubular members together and is directed particularly to theapplication of such means to storage water heaters.

In storage type hot water heaters commonly known as automatic storagetype heaters, the introduction of cold water into the heater tank iscustomarily made through the top of the tank or boiler by means of atube or pipe which extends to or terminates adjacent to the bottom ofthe tank so that as hot water is withdrawn, usually through the top ofthe tank, no intermingling of the cold water coming in, with theoutflowing hot water will occur.

The conventional construction of such storage type water heatersembodies an inlet tank nipple which is secured in the top of the tankand this nipple has extending downwardly therethrough the pipe by whichthe incoming cold water is conducted to the bottom of the tank, suchpipe being known in the tradeas a dip tube. These dip tubes aregenerally made of brass or steel and are of such size as to readilyslide down through the inlet tank nipple and have upon their top ends aflange or flared portion which rests upon the top of the nipple to holdthe tube in position.

It has been found that advantages are to be derived from the use of diptubes made of a suitable plastic and in order to maintain such plastictubes in position or, in other words, to prevent the plastic tubes fromfalling through the tank inlet nipple, the upper ends of such plastictubes have been enlarged and maintained in such enlarged condition forengagement with the top end of the water inlet tank nipple in order toprevent the tube from passing through into the tank.

In many localities it is now required that hot water pipes, particularlyin residences, be of copper and accordingly copper sweat fittings areemployed for coupling the water conducting copper pipe with the waterinlet tank nipple by the employment of an adapter fitting which isscrewed onto the nipple over the enlarged or bulged end of the plastictube. The required connection of the pipe with the copper adapter isthen accomplished in the customary manner by the use of a torch by whichto solder the pipe to the adapter. This use of heat results in thesoftening of the plastic dip tube so that thebulged end thereof is nolonger maintained in place and the tube falls through the tank nippleinto the tank.

In the light of the foregoing, an object of the present invention is toprovide an improved means of maintaining the end of the plastic dip tubeexpanded or enlarged in such a manner that even though the tube maybecome softened when heat is applied to the surrounding adapter, themeans for maintaining the bulge in the end of the tube will not bedestroyed and consequently the tube will maintain the required positionin the nipple.

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therefore, when inserted in the end of the tube, increases the diameterof the latter to an extent which prevents it from passing through theinlet tank nipple. Use has been previously made of an inserted ringmember for this purposebut such ring members are so formed that when theplastic tube becomes softened, by application of heat to the surroundingpipe in the manner above set forth, the inserted ring will not maintainits position as the weight of the plastic tube causes the ring to slipout than the inside diameter of the plastic tube and which,"

of the end of the tube and the tube thus falls into the water tank. i

A further and more specific object of the invention is to provide aninsert ring of new and novel form which, when placed in the end ofthedip tube, will lock itself to the wall of the tube so that even thoughthe substance of the tube may become softened the inserted ring will notescape and accordingly the tube is permanently held in position.

The foregoing objects are attained through the provision of an annulusadapted to position in an end of the plastic tube and having an outsidediameter materially greater than the inside diameter of the tube wherebya portion of the tube wall is forced outwardly to form an annular flangeor head having a diameter'greater than the inside diameter of the tankinlet nipple through which the tube extends, means being provided foreffecting a non-slipping engagement between the annulus and the wall ofthe tube whereby the annulus is prevented from slipping out of positionin the event ,of softening of the tube through the application of heator for any other reason.

In one embodiment of the invention, the annulus is in the form of a thinmetal ring of conical form, the edge of the ringof larger circumeferencebeing provided with teeth which, when the ring is placed in the end of aplastic tube, with the edge of larger circumference directed outwardlytoward the adjacent end of the tube, will penetrate the wall of the tubeand thus hold the annulus in position.

In another embodiment of the invention, the annulus may be formed ofround wire having the surface around the major circumference thereofserrated in a suitable manner to form teeth which maybe disposed at adesired angle for penetrating engagement in the inner surface of thetube in which the annulus is positioned. In either embodiment, theoutside or overall diameter of the annulus is proportioned with respectto the inside diameter of the inlet tank nipple so as to increase theoutside diameter of the end of the tube in which the annulus is placedto a greater radius than the radius of the nipple so that the portion ofthe tube of greater diameter will engage against the end of the nipplefor suspension therefrom.

The invention will be best understood from a consideration of thefollowing detailed description taken in connection with the accompanyingdrawing forming a part of the specification with the understanding thatthe invention is not confined to a strict conformity with the showing ofthe drawing but may be changed or modified within the scope of theappended claims.

In the drawing: I

Fig. 1 is a sectional view through a portion of the top of a storagewater heater tank and through the tank nipple and copper pipe adaptorshowing a plastic dip tube in position in association with a securingannulus constructed in accordance with an embodiment of the presentinvention, the annulus and upper end portion of the plastic tube beingin section.

Fig. 2 is a longitudinal section on an enlarged scale through the upperend of the water inlet tank nipple together with an end of a plastic diptube and one embodiment of the securing annulus therein.

Fig. 3 is a sectional view on an enlarged scale, corresponding to Fig.2, but showing the application of another embodiment of the invention.

Fig. 4 is a view in perspective of the embodiment of the annulus shownin Fig. 2.

Fig. 5 is a view in perspective of another embodiment of the inventionas illustrated in Fig. 3.

Fig. 6 is a view in perspective of a fragmentary detail of the form ofthe invention illustrated in Fig. 5.

Referring now more particularly to the drawing, the numeral 10 in Fig. ldesignates a body representing a portion of the top of a waterreceptacle or tank such, for example, as an automatic storage type hotwater tank. As is well known and as has been previously explained, suchtanks are conventionally equipped in the top wall, with a shortupstanding nipple 12 with which is connected in a suitable manner a coldwater inlet pipe.

As has also been set forth, there is conventionally employed a pipe ortube, defined as a dip tube, which is run downwardly through the nipple12 and has its lower end in close proximity to the bottom of the tank soas to conduct cold water into the lower part of the tank and away fromthe hot Water outlet which is usually at the top.

The structure here illustrated is shown as having applied to the nipple12 a copper adaptor 14 which is threaded onto the nipple and in which issweat fitted an end of a copper pipe 16 which is connected with thewater supply system for the tank.

The numeral 18 designates the plastic dip tube which is run downwardlyinto the tank through the nipple 12 and which is of an outside diameteronly slightly less than the inside diameter of the nipple so as to fitfairly snugly therein.

After the dip tube 18 has been inserted into the nipple 12, the top endof the tube is enlarged to form an encircling flange or bead 18 whichhas an outside diameter greater than inside diameter of the nipple 12 sothat the bead will rest upon the inner edge 12 of the nipple in themanner illustrated.

in order to stifien the head 18' and maintain the same in position toprevent the plastic tube slipping down into the tank, there is provideda suitable annular securing member which has an outside diametermaterially greater than the inside diameter of the tube 18, whereby whenthe annular securing member is inserted into the end of the plastic tube18, it will force the wall of the tube outwardly to form the bead 18' as7 shown.

In the illustration of the embodiments of the invention, the securingmember is shown as having an outside diameter greater than the outsidediameter of the tube 18 and approximately equal to the inside diameterof the nipple 12. However, where the tube 18 is of an outside diameterclosely approaching the inside diameter of the nipple, the insertedsecuring member may be relatively smaller, the only requirement beingthat it be of a sutficient diameter to force outwardly a head 18' of aproper diameter to engage on the top end of the nipple and thus preventthe tube from slipping downwardly.

One embodiment of the securing member is illustrated particularly inFigs. 2 and 4 where such member is generally designated by the referencecharacter M. In this embodiment, the member M is in the form of atapered or substantially conical washer formed of relatively thinmaterial, preferably metal, the body wall 20 being inclined outwardlyfrom the bottom edge 21, which is the portion of the member of smallerdiameter, to the upper or top edge 22 which is the portion of greaterdiameter or circumference.

The top edge portion of the body 20 is formed to 4 provide theencircling array of upwardly and outwardly directed teeth 23.

It will be seen from the foregoing that the member M generally is in theform or design of a crown, the top edge of which has the teeth 23 andwhen the member is forced into the end of a tube of elastic materialsuch as plastic or the like, with the toothed edge directed outwardly orlocated nearest to the end of the tube 18, the end edge portion 18" willbend or curl inwardly across the points of the teeth 22.

It will be seen from the foregoing that when the member M is placed inthe elastic tube in the manner described and illustrated the points ofthe teeth 22 will be pressed into the inner wall of the tube and thusany tendency of the tube to slip downwardly through the nipple 12 willbe resisted by reason of the fact that the securing member cannot enterthe nipple with the thickness of the tube 18 interposed between thetoothed edge of the member and the wall of the nipple. Likewise, thebody of the tube 18 cannot slide down across the toothed edge of themember M since any downward movement of the out-pressed rib portion 18'of the tube will cause the points of the teeth 22 to be forced orembedded firmly into the material of the tube.

In the embodiment of the invention illustrated in Figs. 3, 5 and 6, thesecuring member is designated M and, as shown, is in the form of anannulus formed of wire of suitable weight or gauge. This wire annulus,like the member M, has an overall or outside diameter materially greaterthan the inside diameter of the tube 18 and, in fact, is hereillustrated as having an outside diameter greater than the overalldiameter of the tube 18 and closely approaching the inside diameter ofthe nipple 12.

The member M is illustrated as being formed of wire material of circularcross section although it is to be understood that the invention is notlimited to material of this form.

-In order to firmly maintain the securing member M in engagement withthe inner wall of the plastic tube, the outermost circumferential faceor surface is provided, in a suitable manner, with teeth 24 which arehere illustrated as being elongated in the direction of thecircumference of the member. These teeth 24 may be produced in anydesired form, as by serrating the outer surface of the member as at 24'in Fig. 5 or they may be provided as one or two or more rows of separateout-struck portions of the metal of the ring as indicated at 24", inFig. 6, or the surface of the ring may be grooved circumferentiallyalong one or more paths as desired. In any case, the outwardly directededges thus produced will be pressed, when the annular member is insertedinto the end of the plastic tube 18, firmly against the wall of the tubeand will bite thereinto so that any tendency of the tube to slipdownwardly between the ring and the surface of the nipple will beeffectively prevented.

While the illustration and description of the present invention havebeen confined to its application to an automatic storage type hot waterheater, it is to be understood that the invention is not limited to suchuse but may be used in any other construction where it may be desirableto retain a tube of semi-rigid material in a suspended condition inanother surrounding body, in the manner illustrated.

I claim:

1. The combination with a tube of elastic material and of substantiallyuniform wall thickness, of an annulus positioned in an open end of saidtube and having an outside diameter greater than the inside diameter ofthe tube and maintaining the open end of the tube stretched to anincreased diameter to form an encircling head or collar.

2. A dip tube of elastic material such as plastic and the like, and anannular member disposed in an open end thereof and concentric therewith,said member having an outside diameter greater than the inside diameterof the tube and eflfecting and maintaining the open end of the tube in aradially stretched condition to provide by such stretching an encirclingrib, and means for effecting a nonslipping connection between theannular member and the wall of the tube.

3. The invention according to claim 2, wherein said means comprisesteeth carried by the annular member and directed outwardly forengagement in the inner wall of the tube.

4. In a tank structure of the character stated having a vertical nippleopening downwardly thereinto, a tube of semi-rigid stretchable materialadapted to extend through said nipple, and means for retaining said tubesuspended in and from the nipple comprising an annulus of a greateroutside diameter than the inside diameter of the tube and engaged in anend of and stretching the tube to an outside diameter greater than theinside diameter of the nipple.

5. A dip tube of elastic material such as plastic and the like, anannular member disposed in an open end thereof and concentric therewith,said member having an outside diameter greater than the inside diameterof the tube and maintaining the open end of the tube in a radiallystretched condition to provide by such stretching an encircling rib, andmeans carried by the annular member having contact with the innersurface of the open end of the tube and effecting a non-slippingconnection between the annular member and the said inner surface of theopen end of the tube.

6. The invention according to claim 5 wherein the open end of the tubeis defined by a terminal edge of the tube which is disposed adjacent toand spaced axially outwardly of the tube from the annular member and theinside diameter of both the annular member and the terminal edge of thetube being at least as great as the inside diameter of the tube inwardlyof the annular member.

7. For use in an elastic dip tube, a rigid annular body adapted forinsertion into an open end of such elastic tube to stretch the tube toan increased outside diameter, said annular body being formed of wireand having teeth thereon and therearound on the periphery thereof, saidteeth being in the form'of serrations and projecting outwardly forengagement with the inside surface of the tube in which the ring isfitted to secure the ring against slipping.

8. For use in an elastic dip tube, a rigid annular body adapted for.insertion into an open end of such elastic tube to stretch the tube toan increased outside diameter, said annular body being formed of wireand having thereon and there-around on the periphery thereof one or morerows of separate outstruck portions forming outwardly projecting teethfor engagement with the inside surface of the tube in which the ring isfitted to secure the ring against slipping.

References Cited in the file of this patent UNITED STATES PATENTS743,401 Sherman Nov. 3, 1903 '1,097,701 Yount May 26, 1914 2, ,8 9Landis June 20, 1939 2,241,355 Maclachlan May 6, 1941 2,310,877 SperryFeb. 6, 1943 2,538,375 Montgomery Jan. 16, 1951 2,616,729 Hansen Nov. 4,1952 FOREIGN PATENTS 566,612 Great Britain Ian. 5, 1945 OTHER REFERENCESPublication, Waldes Truarc, copyright ed. 1947, pages 4 and 7. (Copy inDiv. 29 287,, Split Ring Digest.)

